The contract was 5♠X by South, after we had (not surprisingly) bid both minors strongly. Result was 2 down which was a bit disappointing because, as you can see, we missed a slam in either minor (other tables didn't!). It was hard to reach that slam with N-S interference!
I had doubled by way of a Lightner double, asking for a ♥ lead (I expected my K♠ to be finessed out otherwise, although as you can see Declarer had no way to do so). My partner didn't interpret my double as Lightner though, and led a club (naturally). Two heart ruffs, two minor Aces and the K♥ would have been an extra trick for us - but it wasn't to be.
Question: was it correct to assume a Lightner double here (can't remember the complete bidding sequence sorry)? Is it well known? Is it worth discussing this convention with partner beforehand?